Sweet cream is the base of ice cream. You use that to flavor, adding vanilla or chocolate powder to a sweet cream base will give you those ice creams.
Milk ice cream is sweet cream base and then add milk flavor. I think they use condensed milk to pull it off, but it's weird and the US doesn't sell anything like it at any kind of scale to my knowledge, and I've looked
The other guy is mostly right, but that's not exactly the same thing.
It's like... Concentrated milk? Think they add condensed milk or something, its like milk, but more. Like the cream stuff from ice cream shops, but more.